Elk Grove, California, a fairly new city incorporated on July 1, 2000 in Sacramento County, is the nation's fastest growing city over 100,000 residents based upon the most recent year of data, according to the U.S. Census Bureau. Elk Grove, which was a small town with only one stop light and home to my high school in the late 1980s, grew from 100,686 on July 1, 2004 to 112,338 on July 1, 2005, a 12% increase, as it becomes a major suburban center.
Other fast-growing cities include 2) North Las Vegas, Nevada; 3) Port St. Lucie, Florida; 4) Gilbert, Arizona; and 5) Cape Coral, Florida. Florida has three cities in the top ten. More from the Bureau.

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I hear the fastest growing city in the U.S., is CHULA VISTA, CA (San Diego county) !
Elk grove sucks
I agree with John Doe. Livin’ in the EG sucks hard…
I think is Mexico City. America is not a country is a Continent.
I think this might not be true anymore. I know, as a Tampa Bay resident, people can’t leave out of Port St. Lucie, or Cape Coral fast enough. They’re heading north to Georgia or the Carolinas….the economy is dying down here in Florida…..
Your right Jason as I am leaving in less then a month from PSL to go back up north. I have been here 1 1/2 years and the economy is AWFUL. The public Schools are the worst, there is flooding issues and the people are rude. Makes it a real inviting place to live…NOT! I cant even believe Port Saint Lucie made that list. The worst decision I have ever made in my life was to move here.
Elk Grove sucks big fat donkey dick! Mindless ghetto SCUMBAGS!
Elk Grove is a sinkhole of an excuse for a Nor-Cal city. Once you fall in, it is nearly impossible to get out. The police will bankrupt you with endless traffic tickets as you try to take your children to school. Then once you are at the schools for a couple of years you realize the public schooling system is corrupt and inept. Elk Grove suffers from an acute case of myopic nepotism which will sacrifice competency at any public or private sector position for clique/familial relationships. If you are part of the EG/Sac old families then you will have it made here. If not, then you had either be a minority or celebrity. All others are not welcome. This cancerous community will take every single second of time you volunteer or money you donate and bleed you dry with no thank you or glimmer of appreciation. DO NOT MOVE HERE!